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Crimping Connectors

I have found so many poorly done crimps that I have become a believer that proper crimping is a fundamental part of professional fireplace service.

I have spent more hours, than I care to admit, studing crimping tools and connectors. I am now just starting to sort it out. I wish I knew someone to help me get a grasp of it. But I think I have begun to formulate how to address this issue.

I don't think that it is necessary to buy aerospace quality crimping tools, (but if any one industry could justify it, it would be us guys that work on milivolt systems every day).

I do think that you do need a good quality ratcheting crimper. I also have a theroy that the quality of the connector fittings are also a big factor, albeit much lessor of a factor than the crimper itself.

Another thing, I was taught early on that improper wire size can cause excessive milivolt loss in moderate or long runs. I have found this to rarely be an issue. I have seen some drop but found that the wire size was not the biggest contributer, moreover, the drop is a constant that may be able to be disregarded in an intermittent operation problem.

We all know if the pilot gen is strong and there is not enough power back to the valve it is usually switches, (limit, control). I do believe that connectors are also an often overlooked issue. I have rambled on a little but that is my point.

We end up replacing a lot of the crimp connectors when we do service calls due to millivolt loss. Some of techs just put wire nuts on instead, they seem to work better and last longer then the crimp connectors.

I once had an intermittent main burner operation problem and I couldn't track it down. Come to find out, on BOTH connectors for the remote, they had inserted the wire's insulation too far into the connector and it was crimped on the insulation, not the wire. I've seen this issue several times. Must have been made the day after Cinco de Mayo.

I've anso run across people in a hurry when installing a wall switch and screw the insulation under the screw head.....that works....sometimes !!!

Be sure to use the correct anvil for insulated versus non-insulated terminals. Always tug on the terminal to ensure a tight fit.

Understand most ordinary electrical components were designed for 115-125 vac. We're operating at 1/5th a one volt DC for millivolt systems except TC cutoffs work at <30millivolts DC. Proper materials with proper connections are critical. Don't use cheap terminals. They can oxidize and their seams are usually not brazed so they will open up resulting in poor contact. Spend the money on a good crimper and don't cry over paying $1 each for good terminals--that's a lot cheaper than a callback.

millivolt connectors

Hey Crazymonk, appreciated what you said but just wanted to share what I"ve found too. Years ago I had a space heater in garage that guy had aprox.5ft. of 20 ga.braided speaker wire to tstat.W/meter checked voltage drop.Iused an adapter to check gas valve electromagnet mv too.Installed 18 ga.wire and issue settled.Every connection is considered to be a "power passing" device as opposed to a "power consuming"device but w/mv system that goes out the window.
If you work on kitchen equip.specifically deep fryerwhich is mv and has tstat,limit and more connections than a fireplace and theres always greasey coating on everything you see importance of every connection.A bunch of these I,ve SOLDERED the connections.
I,ve got a question for you;do you know where I can look for info.on ventless fireplace?A few yrs. ago the CGA didn,t allow but is there new technology w/ie.low oxygen sensor safties or whatever?Also what technology do they use to provide a more luminescent type of flame rather than compromising primary air? This open to any hearth techs.Thanks.

more VF

Dfelt, you can check with the Ventfree Alliance for a pro VF opinion or you can read the rest of the Internet for an anti-ventfree opinion.

VF are listed to ANSI Z21.11.2, which has required an Oxygen Depletion Sensor safety pilot for over 20 yrs. The ODS has been out since 1980 so it ain't exactly "new" technology.

They wouldn't be able to sell VF fireplaces if they had a solid blue non-luminous flame. They should have blue bases w/ yellow tips and have been this way, also for over 20 yrs. They use precision engineering to achieve this in the lab..................not always achieved in the home. VF are not adjustable in the field. You can replace the ODS pilot assy., valve or burner but that's about it--no adjusting regulators, orifices, air shutters, etc.

I don't know how many poor connections I have found, and yes most were from poor terminal connectors. This is always found using your meter. Most of the time I remove the fitting, brighten the wire and install it on the terminal. Of course that means terminals with screws, which most older systems have. Its amazing how many volts can be picked up when the system is cleaned up.

Crazy,,,,,you've got the best place in the world to purchase good crimpers. Go to the Boeing surplus store, and find what you need. Then go to an electronics supply place and purchase the replacement jaws for them. Had a friend pick me up about 8 different ones and bought the jaws from a supply house in Portland. I got em all, for less than a hunnert dollars,,,,,,,,,,,

One way to outthink people is to make them think you think. They'll think you're not really thinking what you're trying to get them to think you think...........

Understand most ordinary electrical components were designed for 115-125 vac. We're operating at 1/5th a one volt DC for millivolt systems except TC cutoffs work at <30millivolts DC. are there mv specific wall switches?Proper materials with proper connections are critical. Don't use cheap terminals. They can oxidize and their seams are usually not brazed so they will open up resulting in poor contact. Spend the money on a good crimper and don't cry over paying $1 each for good terminals--that's a lot cheaper than a callback.agree with that 100%